SJS and CRC sell secuclips iun there own:

Sjs Link

TBH I think I'm swinging more and more towards the Roadrat. I've yet to hear that I can definately get one via my work's particular scheme, hence still wanting to hear about more "mainstream" possibiities should I have to resort to Halfords.

You can order a Roadrat through Halfords no problem – I ordered mine through my works scheme from there the year before last. I went into the store, told them what I wanted and they put it through on special order. I think I just had to call Cotic first to check on stock.

For what it's worth, I'd say it's a good match for what you're looking for and ticks all the boxes. You will probably need to be careful with tyre choice though given your mixed commute. I run drops and cross tyres on mine and it will go in most stuff, althought it gets a bit sketchy on really rocky trails. Absolutely rips on tarmac, fire roads and smooth singletrack and is a great mud bike.

Oh…and toe overlap has never been an issue on mine, even with the "short" frame.

this is what I got through Cyclescheme last year when faced with similar requirements :

http://www.evanscycles.com/products/cannondale/bad-boy-disc-2010-hybrid-bike-ec020193?utm_source=froogle&utm_medium=froogle&utm_campaign=froogle

This would seem to be just the ticket. Review doesn't specifically mention mudguards, but the concept looks made for these requirements.

Salsa review

Big tyres and mudguards with drop bars on a small sized bike will always give you toe overlap – the Roadrat in flat-barred/long frame guise avoids it because you need more frame stretch to go with the flat bars.